# Take the last line of the top three lines
head -n 3 my.txt | tail -n 1
# Tell sed to "be quiet", and print just the third line
sed -n 3p my.txt
# Tell sed to delete everything except the third line
sed '3!d' my.txt
# Tell awk to print the third input record of the current file
awk 'FNR==3 {print}' my.txt